Commentary
diff --git a/src/core/channel/channel_stack.h b/src/core/channel/channel_stack.h
index 1279fec..5d33ab5 100644
--- a/src/core/channel/channel_stack.h
+++ b/src/core/channel/channel_stack.h
@@ -214,7 +214,8 @@
/* Destroy a call stack */
void grpc_call_stack_destroy(grpc_exec_ctx *exec_ctx, grpc_call_stack *stack);
-/* Ignore set pollset */
+/* Ignore set pollset - used by filters to implement the set_pollset method
+ if they don't care about pollsets at all. Does nothing. */
void grpc_call_stack_ignore_set_pollset(grpc_exec_ctx *exec_ctx,
grpc_call_element *elem,
grpc_pollset *pollset);